What is the difference between high-efficiency motors and ordinary motors? Where is it expensive?
The difference between high efficiency motor and ordinary motor
Ordinary motor: The motor is a device that converts electrical energy into mechanical energy. 70%-95% of the electric energy absorbed by the motor is converted into mechanical energy. This is the efficiency value of the motor, which is an important technical indicator of the motor, and the remaining 30%- 5% of the motor is consumed by the motor itself due to heat, mechanical loss, etc., so this part of the energy is wasted.
High-efficiency motors: Motors with high power utilization are called high-efficiency motors, referred to as "high-efficiency motors."
For ordinary motors, every 1% increase in efficiency is not easy, the material will increase a lot, and when the motor efficiency reaches a certain value, no matter how much material is added, it cannot be improved. Most of the high-efficiency motors on the market today are newer generations of three-phase asynchronous motors, which means that the basic working principle has not changed.
GW High-efficiency three-phase asynchronous motor
High-efficiency motors mainly improve the efficiency of the motor by the following ways
1. Adding materials: increase the outer diameter of the core, increase the length of the core, increase the size of the stator slot, and increase the weight of the copper wire to achieve the purpose of improving efficiency. For example, the Y2-8024 motor increases the outer diameter from the current Φ120 to Φ130. Some foreign countries increase Φ145 and increase the length from 70 to 90. Each motor increases the amount of iron by 3Kg copper wire by 0.9Kg.
2. Silicon steel sheets with good magnetic permeability are used. In the past, hot-rolled sheets with large iron loss have been used, and high-quality cold-rolled sheets with low loss, such as DW470, are now used. Even lower DW270.
3, improve processing accuracy, reduce mechanical losses Replace small fans to reduce fan loss using high-efficiency bearings.
4. Optimize the electrical performance parameters of the motor and optimize the parameters by changing the groove shape.
5, the use of cast copper rotor (process is complex, high cost).
High efficiency motor features
1. It saves energy and reduces long-term operating costs. It is very suitable for textiles, fans, pumps and compressors. It can recover the purchase cost of motor by one year of saving electricity;
2, directly start, or use the frequency converter to adjust the speed, can completely replace the asynchronous motor;
3, rare earth permanent magnet high-efficiency energy-saving motor itself can save more than 15c / o than ordinary motor;
4, the motor power factor is close to 1, improve the quality factor of the power grid, no need to add power factor compensator;
5. The motor current is small, saving transmission and distribution capacity and extending the overall operating life of the system;
6. Power-saving budget: Take the 55-kilowatt motor as an example. The high-efficiency motor is 15% more energy-efficient than the general motor. The electricity cost is calculated at 0.5 yuan per degree. The energy-saving motor can be used to recover the cost of replacing the motor within one year.
Advantages of high efficiency motors
1. Direct start, the asynchronous motor can be completely replaced.
2. Rare earth permanent magnet high-efficiency energy-saving motor itself can save more than 3% of electric energy than ordinary motor.
3. The motor power factor is generally higher than 0.90, which improves the quality factor of the power grid without adding a power factor compensator.
4. The motor current is small, saving transmission and distribution capacity and extending the overall operating life of the system.
5. The drive can realize soft start, soft stop and stepless speed regulation, and the power saving effect is further improved.